LOS ANGELES (CBSLA) — Adults will be able to buy recreational marijuana legally on Monday, Jan. 1, and while this has many people raring to hit the pot shops, there are some things consumers of cannabis, old and new, will just not be able to do under the new law.

California becomes the largest to state to legalize pot for adults, and that has experts, both for and against the move, issuing warnings about the proper, legal ways to consume the substance, which is still illegal under federal law.

“So, what a lot of people don’t realize is that you can’t just smoke marijuana whenever you feel like it or wherever you’d like to,” criminal defense attorney Lou Shapiro told CBS2 News.

For example, people cannot smoke cannabis in cars and are subject to infractions if they do.

Smoking within 100 meters of a school or day care center is also prohibited.

Marijuana will be regulated much like alcohol, Shapiro said.

Adults 21 and over will be able to buy up to one ounce of pot at any state-licensed retailer.

That, in and of itself, may be difficult come Monday, in Los Angeles, anyway.

L.A. has delayed accepting applications for retail licenses until Jan. 3, and only one shop will be legally allowed to sell on New Year’s Day, The L.A. Times reported.

It could actually be weeks until most licensed shops will be open in L.A.

Dina Browner with Alternative Herbal Health Services in West Hollywood will be able to sell legal pot on Jan. 2.

“For so many years, everyone has known how simple it is to go see a doctor and get a little letter, so it hasn’t been an issue for us,” Browner told CBS2. “Do we expect big lines? Yes, we do have a lot of people who have been waiting for this day.”

Shapiro told CBS2 that law enforcement authorities are expecting pot-related car accidents to increase with the change in law.

“While we’ve seen alcohol-related DUIs significantly go down due to Uber and Lyft, on the other side, now, with the legalization of marijuana being so accessible from these shops on the street, marijuana DUIs are definitely going to go up, and we’ll see how far that goes in the criminal justice system,” Shapiro said.

For a comprehensive list of what is legal under the new cannabis law, visit the “Let’s Talk Cannabis” page of the California Dept. of Public Health.